Partial molar volumes of organic compounds in C8 solvents at 298.15 K

Limiting partial molar volumes of n-hexane, cyclohexane, ethyl ether, tetrahydrofuran, pentan-3-one and cyclopentanone in di-n-butyl ether, hexyl acetate and octan-2-ol were determined at 298.15 K from density measurements of dilute solutions carried out with a vibrating-tube densimeter. The solute–solvent interactions and the effects of the local organisation of the solvent around the solute molecules were discussed using the molar, void, and cavity volumes as different estimates of the intrinsic volume of the molecules. The analysis was then extended to the volumetric behaviour of the same solutes in octan-1-ol. The solvents examined interact with the solutes in different ways. The isomeric octanols show the most significant effects, possibly due to their H-bond donor nature. The solute–solvent interactions seem to prevail over the packaging effects in determining the volumetric behaviour of the solutes.